Maps provide a simple, yet powerful visualization method to represent geospatial reality. Since maps are configured to faithfully reflect real-world geography (or attempt to reflect, as effectively as possible, the three dimensional Earth as a two dimensional construct), individuals can intuitively estimate the travel time between two points on a map by measuring the distance between them and multiplying this distance by some scale to determine a “real-world” equivalent. However, other factors such as traffic, variable speed limits, weather conditions, and special events make estimating actual travel time between two points on a map difficult. Urban travel in particular is fraught with traffic congestion and uncertainty.
The apparent distances between places and the variable nature of the time needed to travel between such places regularly bewilders people because geospatially representative maps sometimes fail to represent realistic accessibility. Designers have put considerable effort into creating visualizations of graphs to aid human perception. For example, some real-time mapping systems show roadways with various colors to highlight traffic congestion in an attempt to enhance geospatial information with dynamic geotemporal information. However, people generally do not find such visualization techniques intuitive, resulting in inaccurate travel estimates and unnecessary delay.